Papers by Federico Scarpa
Energy, May 1, 2018
The present paper proposes an analysis concerning the impact of the reduction of the net electric... more The present paper proposes an analysis concerning the impact of the reduction of the net electricity 11 flow between France and Italy due to the phase out of French nuclear power plants. The analysis is
International Journal of Heat and Mass Transfer, Nov 1, 2012
Many studies about heat transfer characterization of single phase fixed bed matrix regenerators a... more Many studies about heat transfer characterization of single phase fixed bed matrix regenerators are devoted to the finding of experimental correlations. Despite several deep investigations, the emerged correlations are not well established, indeed the high complexity of the processes involved, the shape of the solid-fluid interface, the complexity of the geometry of the solid matrix, make accurate experimental data difficult to obtain. The aim of the present work pursuit a double objective: (i) to develop and propose an inverse method to identify h, the fluid-matrix heat transfer coefficient, by means of transient simulated experiments, and (ii) to investigate the sensitivity of the h reconstruction process to the variation of the control input parameters and material properties, in order to find the optimal value of the experimental control variables that allows the identification of this unknown coefficient to be performed with ''minimum variance''. The reconstruction technique is applied to numerical experiments and it is based on the simulated measurements of oscillating temperatures of the fluid at the inlet and outlet of the regenerator. The identification of h is performed by means of an inverse search technique, driven by the difference between simulated measurements and calculated temperature time histories at the regenerator outlet. At first, experiments in different operating conditions are simulated in order to investigate the ability of the algorithm to identify the correct value of h and its uncertainty. Then a parametric study is performed and the optimal control frequency of the known (imposed) oscillating temperature signal at the inlet is found as a function of the mass flow rate, the geometry and other operating and thermophysical characteristics of the system.
Energy, Apr 1, 2021
Abstract The electrification of the road transport sector is seen as a necessary component to the... more Abstract The electrification of the road transport sector is seen as a necessary component to the urban decarbonization. A scenario analysis of electric cars deployment is developed by employing the Long-range Energy Alternative Planning platform to build a bottom-up model to evaluate the contribution to the energy transition in the long term. The difference with similar models available in the literature is represented by a detailed description of the car stock, which comprises twenty-eight categories of cars. The car stock is segmented according to the fuel, i.e., petrol and gasoline, engine displacement, i.e., small and medium, and fuel efficiency according to the Euro standard, i.e., from Euro 0 to Euro 6d. Such features can be applied to any EU country; therefore, the model has a European Union-wise applicability. To show the model effectiveness, an application to the Italian automotive sector focused on the estimation of energy consumption and polluting emissions is proposed in the period 2018–2030. The evolution of the Italian car stock and the corresponding energy consumption, emissions and externalities are estimated. The simulations show that a significant reduction in energy consumption up to 23% and a decrease of emissions is realistically achievable through the deployment of electric cars.
Applied Thermal Engineering, Apr 1, 2013
h i g h l i g h t s < We give preliminary results from a linear reciprocating magnetic refrigerat... more h i g h l i g h t s < We give preliminary results from a linear reciprocating magnetic refrigerator prototype. < The design is intended to process visualization and investigation. < The prototype behavior gives us various suggestions to improve its general performance.
Transportation research procedia, 2020
This paper investigates possible scenarios of electric cars introduction and their impact on the ... more This paper investigates possible scenarios of electric cars introduction and their impact on the Italian electricity system. Given the foreseen increased number of cars until the year 2030, three different scenarios in terms of penetration of electric vehicles have been considered, namely 10%, 20% and 40%. A detailed bottom up energy model of the Italian car fleet has been developed. The car fleet is analyzed in terms of energy consumption, carbon emissions and externalities costs. The scenarios analysis suggests that the introduction of electric cars would always lead to primary energy savings. In particular, the increase of the penetration corresponds to a decrease of primary energy consumption, carbon emissions and externalities costs.
Thermal science and engineering progress, 2022
International Journal of Numerical Methods for Heat & Fluid Flow, Mar 4, 2019
PurposeThe purpose of this paper is to carry out a numerical investigation to study laminar conve... more PurposeThe purpose of this paper is to carry out a numerical investigation to study laminar convection flow of Al2O3-water nanofluids within a three-dimensional rectangular section channel asymmetrically heated.Design/methodology/approachA three-dimensional model of the channel is designed and simulated by using Comsol Multiphysics. The finite elements method is used to perform the numerical simulation. A variety of cases are taken into account by considering Reynolds numbers ranging from 250 up to 1,000, concentration between 0 and 6 per cent, particle dimension of 20, 40 and 60 nm and inlet temperature equal to 293.15 and 320 K. A constant heat flux of 1,000 W/m2is imposed on the top surface of the channel.FindingsThe results demonstrate that nanofluids guarantee improved thermal performances with respect to the base fluid, as shown by the augmented Nusselt number. On the other hand, pressure drop shows a noticeable increase; therefore, an entropy generation analysis is developed to establish optimal conditions for the system under investigation.Originality/valueThe originality of this work consists in the analysis of a three-dimensional asymmetric heated channel with nanofluids in laminar convection. The present work would be beneficial to improve the design of devices with particular focus on solar thermal panel.
International Journal of Refrigeration-revue Internationale Du Froid, Sep 1, 2013
A method is presented and tested which, implemented along with a lumped dynamical model of an inv... more A method is presented and tested which, implemented along with a lumped dynamical model of an inverse cycle, allows for the description of the system with very simple mathematical tools, without any need to possess information about the thermophysical properties of the refrigerant fluid operating in the cycle. The algorithm, based on the fluid independent Carnot cycle, is applied both to a household refrigerator and to a direct expansion, variable capacity, solar assisted heat pump (DX-SAHP). The validity of the approach is established by comparing the numerical results of the proposed simplified approach to transient and time averaged data based on consolidated thermodynamic-cycle simulators which make use of full standard fluid properties description. Simulations comparisons confirm the ability of the proposed model to closely adhere to the dynamic behavior of the considered devices and disclose the opportunity to develop inverse-cycle models so simple to be easily embedded, along with their sensitivity features, in cheap model-based regulators and transient control strategy developments.
Journal of Porous Materials, May 12, 2007
Abstract A typical relation between accumulated liquid, temperature, and vapour pressure characte... more Abstract A typical relation between accumulated liquid, temperature, and vapour pressure characterizes any surface, in particular any porous structure. This relationship is usually described by means of “adsorption isotherms”, which are functions that correlate the amount of liquid in the porous material to the partial pressure of its vapour, for a given constant temperature. Speaking about fibrous insulation materials or building materials, the fluid of interest is simply water. The knowledge of water adsorption isotherms is of great ...
Energy and Buildings, Aug 1, 2017
Energy efficiency is one of the main pillars of the European energy strategy and it involves all ... more Energy efficiency is one of the main pillars of the European energy strategy and it involves all the economic sectors. The present study proposes an analysis of the energy saving opportunities available in the Italian hotel sector, which has a relevant importance in the national context. The paper introduces a comprehensive model of the Italian hotel sector developed in the LEAP (Long-range Energy Alternatives Planning) environment. The first aim is to estimate the baseline of the consumption, then to evaluate the maximum potential energy saving and, finally, to assess the implementation of a realistic energy efficiency scenario. The paper demonstrates that it may be possible to achieve primary energy savings of 1.6 TWh (13%) in 2030 by implementing financially sustainable energy efficiency measures.
International Journal of Refrigeration-revue Internationale Du Froid, Jul 1, 2023
Journal of building engineering, 2020
This paper aims at introducing an approach for improving the renewable sources technologies inclu... more This paper aims at introducing an approach for improving the renewable sources technologies inclusion in the municipality planning process and calls to revisit the current governance to strengthen the implementation effectiveness. The solar energy potential and the local energy requirements of the city of Riva Trigoso are analyzed and two types of solar technologies are tested. An analytical methodology based on the exposition of the buildings present in the considered location is developed. The method allows to identify the areas where it is more convenient to invest and the specific technology to be used. The effectiveness of the optimization method is validated via comparison with random allocation of the same total surface of panels. The results have been translated into GIS maps where the municipality can identify the areas at best solar energy potential and the more suitable technology. The proposed approach can be used for any location and it allows to define detailed scenarios for local energy planning processes.
Frontiers in energy, Jan 21, 2015
Gas market in Europe is experiencing a radical change for different reasons, partially determined... more Gas market in Europe is experiencing a radical change for different reasons, partially determined and accelerated by economic downturn of the last period. In the past few years, many European countries adopted energy policies largely based on the utilization of natural gas. In fact, a sharp increase of the demand was observed and, at the same time, a lot of infrastructures were developed to assure the necessary supply. In the last few years, due to the economic downturn, natural gas demand decreased, causing a consistent oversupply on the market, which altered the consolidated dynamics of the sector. Understanding the changes currently under development in the European gas market is of paramount importance in order to design future strategies for the sector; in particular, it is necessary to understand if the present situation will cause a reshaping of the sector.
Solar Energy, Oct 1, 2013
ABSTRACT Design and control strategy suggestions for direct expansion solar assisted heat pump (D... more ABSTRACT Design and control strategy suggestions for direct expansion solar assisted heat pump (DX-SAHP) water heaters are stated as a result of a novel steady-state primary energy consumption analysis based on a model developed around the fluid-independent Carnot cycle. The study is devoted to devices committed to hot sanitary water production and supplemented by an instantaneous gas burner. The paper addresses several suggestions about the correct design and the optimal working conditions needed to minimize the use of primary energy, based on averaged working conditions. The maximization of primary energy savings has been selected as the criterion to define our concept of “optimal performance” since this approach benefits from the use of a direct language that permits a larger, also non-specialized, audience to acquire the basic concepts of optimal behavior, increasing the transfer of knowledge to actual embodiments. Apart from the particular criterion selected in this study, the focus is on the proposed steady state approach which, without any use of refrigerant fluid properties, allows us to extract general rules as a function of the main features of the plant and of its relevant interactions with the surroundings, making all the relationship between the involved variables explicit and meaningful. Results obtained using the present approach agree with data coming from an already consolidated dynamic simulator.
Applied Thermal Engineering, Jun 1, 2016
The present work presents an investigation regarding the feasibility analysis of a cogeneration p... more The present work presents an investigation regarding the feasibility analysis of a cogeneration plant for a food processing facility with the aim to decrease the cost of energy supply. The monthly electricity and heat consumption profiles are analysed, in order to understand the consumption profiles, as well as the costs of the current furniture of electricity and gas. Then, a detailed thermodynamic model of the cogeneration cycle is implemented and the investment costs are linked to the thermodynamic variables by means of cost functions. The optimal electricity power of the cogenerator is determined with reference to various investment indexes. The analysis highlights that the optimal dimension varies according to the chosen indicator, therefore it is not possible to establish it univocally, but it depends on the financial/economic strategy of the company through the considered investment index.
Renewable Energy, Feb 1, 2018
The present paper proposes an investigation on the application of Al 2 O 3-water nanofluid within... more The present paper proposes an investigation on the application of Al 2 O 3-water nanofluid within a PV/T panel in order to assess the potential to improve the performance of the device. The analysis has been carried out by developing a numerical model by means of the commercial software Comsol. Two dimensional nanofluids laminar convection flows for Re comprised between 250 and 1000, concentration between 0% and 6%, inlet temperatures of 293.15 K and 323 K and particles dimension of 20 and 40 nm have been simulated in an asymmetric heated channel. Under an imposed external heat flux of 1000 W on the top surface of the channel, the results show that nanofluids guarantee better cooling performances, in fact a decrease in top wall temperature of~3 K is observed for an inlet temperature of 293.15 K and a reduction of~5 K is observed for an inlet temperature of 323 K. Nusselt number and average heat transfer coefficient for nanofluids also increase in a range between 2% and 15%. On the contrary, a relevant increase of pressure drops is detected. The combined effect of heat transfer enhancement and pressure drop increase has been investigated by implementing an entropy generation analysis, which highlights that reduction of thermal entropy generation is more significant than the increase of frictional entropy generation.
This paper investigates a strategy for energy saving in the Italian residential sector that inclu... more This paper investigates a strategy for energy saving in the Italian residential sector that includes in the assessment the embodied energy related to the efficiency measures. Simulations are run in three main cities (Milan, Rome and Naples) covering different climate zones. The purpose is, firstly, to estimate the baseline of the buildings energy consumption, secondly, to simulate the implementation of realistic retrofit solutions and, finally, to assess the retrofitting’ embodied energy and its energy payback time. The energy payback is based on the comparison between the net saved operational site energy and the embodied energy of the selected measures. By running the simulations, it is possible to estimate the maximum potential for energy savings and realistic estimation of achievable results in short-medium period. Results show the energy efficiency measures more convenient in terms of energy payback depending on the climate zone. For Naples, a focus on façade insulation has been held and the results defined the optimal material thickness in terms of embodied energy and net saved operational site energy in a life cycle of 15 years.
Energy & Environment, Jul 10, 2018
The present paper analyzes the Italian energy system focusing on the possible energy, environment... more The present paper analyzes the Italian energy system focusing on the possible energy, environmental, and economic effects that the utilization of individual heat pumps for winter heating can produce. To this aim, a model of the Italian energy system is developed by employing the tool EnergyPLAN in order to develop an hourly simulation of the system at country level. Different scenarios in terms of heat pumps penetration, ranging between 10% and 50%, are simulated and sensitivity analyses in terms of average coefficient of performance of heat pumps are performed. The increase of heat pumps generation shows a steadily decrease of fossil fuel consumption for buildings heating, as well as a reduction of carbon emissions. The utilization of heat pumps for buildings heating leads to an increase of 10 p.p. in the load factor of the combined cycle gas turbine thermal power plants. Furthermore, an optimal heat pumps penetration is determined, namely 20%, which minimizes the energy system costs, calculated as the sum of fuel cost and externalities savings.
Renewable & Sustainable Energy Reviews, Oct 1, 2015
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Applied Thermal Engineering, Jun 1, 2023
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Papers by Federico Scarpa